Overview: Diamond, Thin Hard Films and Related Materials
Optical Spectroscopy. Studies of strong bulk and thin film materials:
Stresses in diamond and cBN as a function of temperature.
Defects in strong materials; irradiation effects.
Elastic properties of thin hard films and bulk materials.
Thin film preparation and single crystal growth.
Specialised synthetic diamond probes for radiation dosimetry measurements in X-ray mammography and low energy X-ray spectra measurements.
Cold-cathode electron emission from diamond for X-ray generation.
Thin Hard Films:
Effects of deposition conditions on Thin hard film growth (single, multi-layer) and Diamond like thin films.
Elastic properties of thin hard films and formation/phase transition of new thin hard transition metal nitrides, carbides and carbo-nitrides films using multi-layer deposition and diffusion driven phase transitions.
Effect of Ion implantation on thin hard films and phase transformation.
Stress formation and relaxation of thin hard films by surface Brillouin scattering and X-ray based techniques.
Experimental Condensed and Soft matter Physics/ Material Physics/ Nanoscience/Nanotechnology:
Graphene, Graphene-nanoflakes (GNFs) with silicon/nitrogen/hydrogen functionalisation, Carbon nano-balls (CNBs), Carbon nano-particles (CNPs), Carbon quantum dots (CQDs), Carbon Nanotubes (CNTs) with nitrogen /Cl2 /O2 funtionalisations. Amorphous carbon (a-C), Graphite, Diamond like carbon (DLC) with silicon/nitrogen functionalisation, Boron-carbon-nitride (BCN) alloys thin films, Ultra-thin tetrahedral carbon (ta-C) and Ultra-nano-crystalline diamond (UNCD) thin films.
ZnO-nanowire(NWs)/nanorods(NRs)/quantum dots(QDs) with/without Au, Co, Mg doped and Group III-Nitrides nanorod.
Electronic/photovoltaic materials: Polycrystalline Oxides (SnO2, CuO, ZnO etc), Metallic Sulphides (SnS, SnS2, CuS, MoS2, CdS, ZnS, and mixed ternary CdxZn1-xS) and nanocrystallites (CdSe CdTe)
Ceramic & PZT (Bulk and thin films): Fe3O4:Al, Pb1-xCaxO3, Pb(ZrxTi1-x)O3 and BaTiO3; High density and High k SiO2.
Thin film deposition processes that are used for those materials are RF Magnetron Sputtering, dip coating and spin coating, CVD/PECVD, ECR and Electro deposition methods/techniques.
Characterisations were performed using UV-VIS, FTIR, Raman, AFM/STM, XRD, XPS, SEM/EDS, Profilometry, NMR, Synchrotron Radiation based Spectroscopy / Microscopy (XANES, Valence-Band PES, PEEM, SPEM), Electron Field Emission, Electrical and thermal transport, Magnetic properties, Piezo-response properties for PZT thin films, Mechanical (Hardness and Young’s modulus) behaviors.
Optical Spectroscopy. Studies of strong bulk materials, single crystals, and nanostructured films:
Elastic properties of strong 1D materials measured using optical spectroscopy
Optical studies of implanted ions and formation or re-growth of buried interfacial layers, elastic properties of buried layers and related processes in CVD diamond.
Brillouin scattering study of generating enhanced SAW frequency in films deposited on elastically hard substrates, and temperature-dependent behaviour of such SAWs.
Ion beam modification of Materials. Enhancing the strong properties of materials by ion implantation:
Study of the radiation damage in diamond caused by ion implantation using Raman spectroscopy and HRTEM.
Electrical, optical and elastic properties of ion implanted materials and the formation nanoparticles and/or phase transformation induced by ion implantation and annealing.
Elastic and electronic properties of the diamond metal interface as calculated by DFT and experimental observation by Raman and Surface Brillouin Spectroscopy.
Ion Interactions with Solids. Studies of surface properties and ion-implantation damage in diamond:
Identity and location of foreign atoms on diamond surfaces.
Electron microscopy of ion implantation damage in annealed diamond.
Surface band-gap of diamond by optical reflection.
Ion beam modification of boron nitride and boron suboxide.
Colloidal metal nanoparticles in hard ionic oxides.
Focus Area Co-ordinator
Prof. S.R. Naidoo
Prof. J.D. Comins
Prof. T.E. Derry
Dr R.E. Erasmus
Dr B. Mathe
Prof. D. Wamwangi